ST. LOUIS (AP) - Harold L. Volkmer, a 20-year Democratic congressman from northeast Missouri known for his advocacy of the rights of gun owners, has died. He was 80.

Volkmer died Saturday at a Hannibal nursing home after several bouts of pneumonia, the James O'Donnell Funeral Home in Hannibal said.

"He was just a wonderful man," Mary Ann Viorel, Marion County collector, said Monday. She was the wife of the late Lee Viorel, who was Volkmer's congressional campaign manager and district administrator. "I greatly admired his moral values, and that's what he based all of his government actions on."

Volkmer was born in Jefferson City. After a stint in the Army and graduation from the University of Missouri School of Law, he moved to Marion County, first to Palmyra and then to Hannibal. He was elected county prosecutor in 1960 and served in that role until his election to the Missouri House in 1966.

In 1976, Volkmer won election to Congress f or the 9th District after veteran lawmaker William Hungate retired. Volkmer served on several committees, including Judiciary, Agriculture, and Science and Technology. He chaired the Space Subcommittee when the space station was launched, and for many years chaired the Agriculture Subcommittee on Small Farms and Forests.

But he earned a reputation in Congress for his unwavering support of gun rights - often in contrast to leaders of his own party. He sponsored the landmark Firearm Owners Protection Act in 1986 that became known as the Volkmer-McClure Act, which reduced federal restrictions on interstate sale of long guns and ammunition. The Senate co-sponsor, Republican James A. McClure of Idaho, died in February.

After leaving Congress, Volkmer was elected to the National Rifle Association Board of Directors and held that role for 12 years, until 2009. He remained on the NRA Executive Council until his death.

Volkmer was also instrumental in passage of legi slation widening U.S. 61 to four lanes, and funding for a flood levee to protect Hannibal's downtown that includes the Mark Twain Boyhood Home and Museum. The levee was completed just months before the Great Flood of 1993. He also played an important role in the passage of the Flood Relocation Act, which provided federal money to move people and, in some cases, entire communities out of the flood plain.

"Harold Volkmer was a man of great passion whose dedication to public service and to the people of the 9th District serve as an example to me of how to be an effective member of Congress," current 9th District Rep. Blaine Luetkemeyer, a Republican, said. "Harold was both a statesmen and gentleman, and will be sorely missed by the people of the 9th District."

Volkmer's wife, Shirley, died in 1995, and in 1996, he lost his re-election bid to Republican Kenny Hulshof.

Volkmer married Dian Poole Sprenger in 1997 and she survives, along with three children, four g randchildren and three great-grandchildren.

A rosary service will be at 4:30 p.m. Tuesday at the O'Donnell Funeral Home in Hannibal, followed by visitation from 5 p.m. to 8 p.m. A funeral Mass will be at 10 a.m. Wednesday at Holy Family Catholic Church in Hannibal, with burial at the church cemetery.